Removable transmission for use with a powered surgical tool, the transmission shaped to extend above the tool, and system

ABSTRACT

An irrigator that is powered by a surgical tool capable of driving an implement. The irrigator includes a pump contained in a pump housing adapted for attachment to the tool. The irrigator includes a tip assembly connected to the pump by a flexible supply tube. Thus the tip assembly can be position against tissue against which the irrigating fluid is to be applied without having to likewise position the tool and the pump.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/656,798, filed on Mar. 13, 2015, which is a Continuation ofPCT/US2013/059669 filed on Sep. 13, 2013, which claims priority fromU.S. Provisional Application No. 61/701,216 filed on Sep. 14, 2012, eachof which is hereby incorporated by reference in its entirety.

BACKGROUND

In many surgical and medical procedures, an irrigator is employed todeliver fluid to a particular location on or in the body of a personreceiving medical attention. For example, during orthopedic surgery, anirrigator is employed to deliver pressurized pulses of water or salinesolution to an exposed surface of the bone in order to clean the bone.There are also some non-surgical procedures performed which likewisemake it desirable to apply pulses of water to a specific site on anindividual's skin. Thus, if an individual is suffering from some type ofbed sore or some other type of skin wound, it is a common practice touse an irrigator to clean the wound prior to applying a dressing to thewound.

A common type of medical/surgical irrigator includes a handpiece towhich a tip assembly is selectively attached. Inside the handpiece is asmall pump that periodically delivers a quantity of pressurized fluid.Also internal to the handpiece is a motor that drives the pump. Thefluid is discharged through a discharge tube integral with the tipassembly to the selected site on or in the patient. These irrigatorsdeliver fluid in pressurized pulses for two reasons. One reason is thatfluid pulses quickly strike the site to which they are applied and leavethe site; this action fosters the desirable removal of debris from thesite. Secondly, the discrete fluid pulses do not obstruct the view ofthe site as much as it can be obstructed when exposed to a continuousflow of pressurized fluid.

Most irrigator handpieces, in addition to having a conduit through whichthe sterile fluid is discharged, have a conduit through which thedischarged fluid is removed from the site to which it is applied.Typically, the fluid is initially withdrawn from the site through asuction tube, also part of the tip assembly. The fluid, as well as anydebris in the fluid stream, then flow through a conduit integral withthe handpiece. The handpiece suction conduit is connected to a secondsuction tube that is connected to a suction system separate from theirrigator. Thus, given their ability to essentially simultaneously cleana site on a patient and remove the debris generated by the cleaningprocess, it should be readily apparent why irrigators have become usefultools for facilitating many medical and surgical procedures. One suchirrigator is disclosed in the Applicant's U.S. Pat. No. 6,099,494 PULSEDIRRIGATOR USEFUL FOR SURGICAL AND MEDICAL PROCEDURES, the contents ofwhich are explicitly incorporated herein by reference.

Many available medical/surgical irrigators work well for the purposesfor which they are designed. One particular disadvantage is associatedwith the cost of providing these irrigators. For an irrigator to bereusable, it must be able to withstand the rigors of autoclavesterilization. In an autoclave sterilization the irrigator would besubjected to an atmosphere saturated with water vapor (steam) at atemperature of 110° C. or more and at a pressures of 180 kPA and higher.It is expensive to provide an irrigator with internal components able tofunction after being placed in this type of environment. Furthermore, ithas proven difficult to clean, decontaminate and sterilize the conduitsintegral with an irrigator through which the irrigating fluid isdischarge and the fluid and waste extracted by the suction process iswithdrawn. Accordingly, presently many irrigators are provided assingle-use disposable units. These units have proven costly tomanufacture because they include both a pump and a motor that drives thepump.

One solution to reducing the costs of these irrigators is to provide aconsole with the irrigators. Internal to the console is a motor. Themotor drives a pump. Since this console is located outside of thesterile field, the console and its components are not subjected to therigors of autoclave sterilization. The irrigator, essentially ahandpiece to which a tip is attached, is removably coupled to theconsole by a set of tubes. These pumpless and motorless irrigators areless expense to provide than irrigators that include these components.Some of these irrigator systems actually predate irrigators that includepumps and motors. One such assembly is disclosed in the Applicants'Assignee's U.S. Pat. Nos. 5,046,486 and 5,269,750 the contents of whichare explicitly incorporated herein by reference.

These irrigators have their own disadvantages. Specifically, theseirrigators require their own consoles. Thus to use one of theseirrigators it is necessary to add another unit, an irrigator console tothe surgical suite. Having to provide this console adds to the cost ofoutfitting the operating room. Alternatively, a facility can have lessirrigator consoles than it has operating rooms/treatment rooms in whichan irrigator may be used. This would then require the medical personnelto ensure that, prior to the start of the procedure in which anirrigator will be used to ensure that the console for the irrigator isin place. If the console is not in place, effort must be spent settingup the console prior to the start of the procedure.

It has been suggested to use a powered surgical tool to power a medicalirrigator. One known system includes an adapter that extends forwardfrom the body of the tool. The adapter includes a gear assembly thatconverts the rotary motion of the shaft integral with the tool motorinto a reciprocating motion. A pump is removably attached to thisadapter. This system eliminates the need to provide each irrigator withits own motor. However the known version system is believed to berelatively heavy and bulky. For example, the power tool, which must beheld and positioned, typically with just one hand, can weigh in excessof 1 kg. Having to hold and position this tool with a single hand canmake the system ergonomically difficult to use. Further, if thepractitioner needs to hold the tool steady, such as at specific surgicalor wound site for anything more than one or two minutes, thepractitioner can start to experience muscle strain and fatigue.

SUMMARY

This disclosure is related to a new and useful medical/surgicalirrigator assembly. The irrigator assembly of this disclosure includesan irrigator handpiece that is economical to provide and that does notrequire a console designed solely or primarily for use with theirrigator.

The irrigator assembly of this disclosure includes a handpiece. Alsopart of the irrigator assembly of this disclosure is a pump unit.Typically, the pump unit is contained in a pump housing that is separatefrom the handpiece. The assembly of this disclosure also includes apowered surgical tool that includes a motor. The tool is the type oftool able to drive some type of cutting implement that is typicallyapplied directly to a surgical site. The pump unit and more particularlythe pump housing is designed to be releasably attached to the poweredsurgical tool. When the pump housing is so attached to the surgicaltool, the motor internal to the tool drives the pump.

To drive the cutting implement, the powered surgical tool has a couplingassembly. The coupling assembly includes components capable ofreleasably holding the cutting implement to the tool so the tool motorwill drive the implement.

In some versions of this disclosure, the pump housing is designed to befitted to the surgical tool so that housing can be in one of a pluralityof different orientations relative to a fixed point on the tool. Thisfeatures facilitates the configuration of the irrigator assembly of thisdisclosure so the components are positioned relative to each other in anarrangement that is most ergonomic and/or minimal inconvenient for theparticular practitioner and/or the procedure in which the assembly is tobe used.

An alternative version of the irrigator assembly of this disclosureincludes a transmission and a pump cassette. The transmission fits ontop of the powered surgical tool. The pump cassette is disposed on topof the transmission. The rotational moment from a spindle internal tothe tool is, by the transmission converted into a reciprocating motion.The reciprocating motion drives a pump internal to the cassette.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure is pointed out with particularity in the claims. Theabove and further features and benefits of this disclosure areunderstood from the following Detailed Description taken in conjunctionwith the accompanying drawings in which:

FIG. 1 depicts the major components of the medical/surgical irrigatorassembly of this disclosure;

FIG. 2 depicts a powered surgical tool;

FIG. 3 is an exploded view of the pump of this disclosure;

FIG. 4 is a perspective view of the pump;

FIG. 4 is a perspective view of the distally directed shell of the pump;

FIG. 5 is a perspective view of the inside of the pump proximal shell;

FIG. 6 is a proximal view of the inside of the pump distal shell;

FIG. 7 is a side plane view of the pump drive shaft;

FIG. 8 is a perspective view of the actual pump unit internal to thepump;

FIG. 9 is a cross sectional view of the pump unit;

FIG. 10 is an exploded view of the wand and tip assembly;

FIG. 11 is a side perspective view of the wand and tip assembly with oneof the wand housing shells removed;

FIG. 12 depicts how the pump may be coupled to the surgical tool in anorientation different from the orientation of FIG. 1;

FIG. 13 is a perspective view of an alternative pump assembly of thisdisclosure;

FIG. 14 is an exploded view of the transmission of the pump assembly ofFIG. 13;

FIG. 15 is a side view of the inside of one of shells forming thehousing of the transmission of FIG. 14;

FIG. 16 is a perspective view of the transmission drive link;

FIG. 17 is an exploded view of the pump cassette of the assembly of FIG.13;

FIG. 18 is a perspective view of the pump cassette;

FIG. 19 is a perspective view of the inside of the bottom shell of thepump cassette;

FIG. 20 is a plan view of the inside of the top shell of the pumpcassette; and

FIG. 21 is a perspective view of the latch internal to the pumpcassette.

DETAILED DESCRIPTION

I. First Embodiment

FIG. 1 depicts the basic components of a medical/surgical irrigatorassembly 30 of this disclosure. Assembly 30 includes a wand 52. A tipassembly 58 is removably attached to and extends forward from the distalend of the wand 32. (In this document “distal” is understood to meanaway from the front of the practitioner holding the wand, towards thesite on the patient to which the wand is directed. “Proximal” meanstowards the front of the practitioner, away from the site on the patientto which the wand is directed.) The tip assembly includes a dischargetube 59. Irrigating fluid flow from a source 38 through a pair of supplytubes 40 and 50 to the wand 52. The irrigating fluid flows out of thewand into the tip assembly 58. The fluid is discharged out of the distalend of the tip assembly discharge tube 59 to the on-patient site towhich the practitioner applies the tip assembly. A spray shield 57, notpart of the present disclosure, is disposed over the distal end of tipassembly 58.

A pump 48 is located between supply tubes 40 and 50. Pump 48 suppliesthe motive power that pumps the irrigating fluid through tube 50, thewand 52 and out of the tip assembly 58. The pump 48 is removablyattached to a powered surgical tool 44. Tool 44 can be used to drive acutting implement used to accomplish a medical/surgical task. Internalto tool 44 is a motor 46. These implements include reamers, wiredrivers, a drill or a saw blade. Motor 46 supplies the mechanical energythat actuates pump 46.

Tip assembly 58 includes a suction tube 64. Suction tube 64 isapproximately parallel with and located above discharge tube 59. Webs 63(identified in FIG. 10) hold tubes 59 and 64 together. Tip assemblysuction tube 64 is connected to a suction tube 66 the distal end ofwhich is disposed in wand 52. Suction tube 66 extends proximally fromthe wand 52. The proximal end of the suction tube is connected to adevice 72 that draws a suction. When irrigator assembly 30 is useddevice 72 is typically actuated. Once the fluid discharged from the tipassembly strikes the tissue against which the tip assembly is applied,suction device 72 draws the fluid away from tissue through suction tubes64 and 66. The suctioned fluid is collected in a container 70.

Powered surgical tool 44 is a sterilizable, reusable powered surgicaltool. Here, “sterilizable” means the tool is able to withstand therigors of a sterilization process that allows the product to be used fora medical or surgical process. One such sterilization process is anautoclave sterilization processor wherein the product being sterilizedis expose to supersatured water vapor (steam) at a temperature in excessof 110° C., at a pressure of 180 kPa and higher. As seen in FIG. 2, tool44 includes a tool body 45. (There are some aesthetic differencesbetween the tool body of the tool of FIG. 1 and the tool of FIG. 2.) Inthe depicted version of the disclosure, tool body 45 is pistol shaped.The body has a barrel 65 and a handgrip 69 that extends downwardly fromthe barrel. Motor 46, represented as a dashed line cylinder, is disposedin the barrel 65. A drive spindle 68, shown in dashed lines, extendsforward from the motor 46. In one version of the disclosure, spindle 68has a closed end bore that extends inwardly from the distally directedface of the spindle. The bore of the drive spindle 68, in cross section,is hexagonal.

Tool 44 includes a coupling assembly. In FIG. 2, the coupling assemblyis represented by a sleeve 73 that extends forward from the distallydirected face of body barrel 65. In one version of the disclosure, pins(not illustrated) extend inwardly from opposed inner surfaces of sleeve73. The pins are also part of the coupling assembly. The drive spindle68 is accessible through the axial opening through sleeve 73.

The drive spindle 68 and the coupling assembly are collectivelyconfigured to releasably receive a cutting implement. The cuttingimplement may be an actual device that is applied to a site on thepatient to perform a medical/surgical task. One such cutting implementis a reamer shaft. Alternatively, the cutting implement may be some sortof front end attachment. The attachment functions as an intermediatetransmission unit that transmits the rotary motion of the tool drivespindle 68 to the actual cutting implement that is applied to thepatient. One such front end attachment is a wire driver. As its nameimplies the wire driver drives, advances, a wire distally forward so thewire can be secured into bone. Drive spindle 98 is configured toreleasably be coupled to and drive the cutting implement. The couplingassembly releasably holds the cutting implement to the tool 44 and, morespecifically, the driven portion of the cutting implement to the drivespindle 68.

A battery 74 is removably attached to the butt end of tool handgrip 69.Battery 74 is supplies the electrical energy that powers tool motor 46.A trigger 76 is moveably mounted to the handpiece body 62. In thedepicted version of the disclosure trigger 76 extends forward from adistally directed face of the handgrip 69 a short distance below barrel65. Disposed inside the handgrip is a control module 80. Both the motorwindings and the battery 74 are connected to the control module 80.Control module 80 also includes components that monitor the displacementof trigger 76. The practitioner actuates the tool motor by selectivelydepressing trigger 76. In response to the displacement of the trigger,the control module selectively applies current from the battery to themotor so as to actuate the motor. One such handpiece is disclosed in theApplicant's Assignee's U.S. Pat. No. 7,638,958, the contents of whichare incorporated herein by reference. Battery 74, like tool 44, canwithstand the rigors of autoclave sterilization. The exact structure ofthe tool, including its coupling assembly and the battery 74 are notpart of the present disclosure.

From FIG. 3 it can be seen that the pump 48 includes a housing 86.Internal to housing 86 is the actual pump unit 88 (FIG. 8). Housing 86consists of first and second shells 92 and 142, respectively. Bothshells 92 and 142 are formed from plastic such as ABS. Shells 92 and 142both can approximately be considered an oval shape. The proximallydirected shell, shell 92, now described by reference to FIGS. 3, 4 and5, includes an outer panel 93. A rim 94 extends distally forward aroundthe outer perimeter of panel 93. Proximal shell 92 is formed so thatthere are a number of arcuately shaped indentations in rim 94. A firstindentation, indentation 95, is located in one section of the rim whereend section of the rim curves into a side section. A second indentation,indentation 96, is formed in the rim so as to be on the same side ofshell 92 and at the opposite end of the shell from where indentation 95is located. A third indentation, indentation 98, is formed in end of therim adjacent second indentation 96. A fourth indentation, indentation102 is located in the rim 94 so as to be located at the same end ofshell 92 as first indentation 95 and on the opposite side of the shellas the first indentation 95.

A number of webs extend distally forward from the inner surface of panel93. Specifically, two parallel webs 106 extend inwardly from the paneland one of the inner surfaces of rim 94 along one of the side surfacesof the shell 92. Each web 106 is formed to have an arcuate cutout 108(one identified). Cutouts 108 are generally aligned with rimindentations 95 and 96. Two parallel webs 110 extend inwardly from therim such that webs 110 are located along the same side of the shell aswebs 106. Webs 110 are longer in length than the adjacent webs 106. Eachweb 110 is defined to form first and second arcuate cutouts 112 and 114,respectively. Each web cutout 112 is located close to the adjacentsection of the rim 94 from which the web 106 extends. Web cutouts 112are generally aligned with the cutouts 108 integral with the adjacentwebs 110. Web cutouts 114, (one identified) which are generally alignedwith each other are located proximal to the center of shell panel 93 soas to be aligned with rim indentation 98. Two parallel webs 118 extendoutwardly from the section of the rim 96 opposite the rim section fromwhich webs 106 extends. Each web 118 is formed to have an arcuate cutout120. Cutouts 120 (one identified) are generally aligned with rimindentation 102.

Proximal shell 92 is further shaped to have a pylon 124 that isgenerally rectangular in shape. Pylon 124 is located between the endsection of the rim 94 in which third indentation 98 is formed and theadjacent web 110. The pylon 124 is further formed to have an inwardlydirected closed end rectanguarly shaped slot 126. Shell 92 is furtherformed so that the distally directed face of pylon 124 has a concaveprofile, not identified. The concave portion of pylon 124 is generallyaligned with rim indentation 98 and cutouts 114 integral with webs 110.Three bosses 130 (one identified) also extend outwardly from thedistally directed surface of shell panel 93. Each boss 130 has a multisection bore, not identified. Proximal shell 92 is formed so that thelargest diameter section of each boss bore is the most distal one of thebore sections.

A coupling member is formed integrally with and extends outwardly fromthe proximal shell 92. This coupling member is designed to engage thehandpiece coupling feature so the pump housing can be releasablyattached to the tool body 62. In the depicted version of thisdisclosure, this coupling member is a sleeve 134 that extends proximallyoutwardly from the outer surface of shell panel 93. Sleeve 134 is shapedto closely slip fit within tool sleeve 73. The outer surface of sleeve134 is formed to have two diametrically opposed indentations 136 (oneseen in FIG. 3). Each indentation 136 extends longitudinally distallyforward from the proximal end of the sleeve 134. Each indentation 136has a detent 138. Indentations 136 and detents 138 are shaped to receivethe pins internal to the tool sleeve 73 that are part of the toolcoupling assembly.

Shell sleeve 134 is further formed to have a multi-section through bore140 (FIG. 5) that extends axially through the sleeve. Bore 140 is formedso that the bore section with the smallest diameter is located adjacentthe proximal end of the sleeve 134. Above the opening into sleeve bore140, the proximal shell 92 is shaped to have two parallel ribs 141. Ribs141 are parallel to and equal spaced apart from the major axis acrossthe proximal shell 92.

Shell 142 is shaped to fit against shell 92. Shell 142 as seen in FIGS.3 and 6, has an outer panel 144 that is in the form of elongated dome. Arim 146 extends proximally around the outer perimeter of panel 144. Whenpump 48 is assembled, distal shell rim 146 seats against proximal shellrim 94. Distal shell 142 is shaped so as that there are four arcuatelyshaped indentations in the rim 146. A first indentation 150 is locatedso that when the pump is assembled the indentation 150 forms an openingwith indention 95 in rim 94. A second indentation 152 is located so thatwhen the pump is assembled the indentation 152 forms an opening withindention 96 in rim 94. A third indentation 154 in rim 146 is located soas to form an opining with the third indentation 98 of rim 94. A fourthindentation 156 is located so that when the pump is assembled theindentation 156 forms an opening with indention 102 in rim 94.

Distal shell 142 is further formed so that six webs extend proximallyfrom the inner surface of shell panel 144. Two of the webs, webs 160,are positioned so as to each be in registration with a separate one ofthe webs 106. Two of the webs, webs 162, are positioned to each be inregistration with a separate one of the webs 110. More particularly,each web 162 is in registration with the section of the complementaryweb 110 that defines the web cutout 114. The remaining two webs, webs164, are positioned so as to each be in registration with a separate oneof the webs 118 integral with proximal shell 92. Each web 160, 162, and164 is formed with an arcuate cutout, (cutouts not identified). Thecutouts integral with webs 160, 162, and 164 are positioned to becontiguous with the cutouts 108, 114, and 120, respectively integralwith the proximal shell 92.

Three posts 168 extend proximally from the inner face of shell panel144. Posts 168 are positioned so that when pump 48 is assembled, eachpost 168 seats in the largest diameter section of the bore of a separateone of the proximal shell bosses 130. Each post 168 is formed with aclosed end bore 170. Upon assembly of the pump fasteners 172 extendthrough bosses 130 into posts 168 to hold shells 92 and 142 together.

A boss 174 also extends proximally from the inner face of shell panel144. Boss 174 is positioned so that when the pump is assembled, boss iscentered on the extension of the axial line through sleeve bore 140.Boss 174 is formed to have a closed end axially extending bore 176. Notidentified are the reinforcing flanges that extend from shell panel 144to the outer surface of boss 174.

Pump 48 includes a single-piece drive shaft 180 best seen in FIGS. 3 and7. Drive shaft 180 is formed from a plastic such as 10% glass fillednylon. The drive shaft 180 is shaped to have a foot 182. The foot isshaped to be releasably coupled to the tool spindle 68. In the versionof assembly 30 wherein the tool spindle has a hexagonal bore, driveshaft foot 182 is, in cross section hexagonal in shape and dimensionedto closely slip fit in the drive spindle bore. Extending distally fromfoot 182, drive shaft 180 has a torso 184. Torso 184 is cylindrical inshape and coaxial with foot 182. Torso 184 is dimensioned to closely fitin one of the sections of sleeve bore 140. Torso 184 functions as a lowfriction interface between the rotating drive shaft 180 and the staticpump proximal shell 92.

A neck 186 extends distally forward from drive shaft torso 184. Neck 186is coaxial with and smaller in diameter than torso 184. Distally forwardof neck 186, the drive shaft 180 is formed to have a cylindrical head188. Head 188 has a diameter slightly less than that of torso 184,greater than that of neck 186. The drive shaft 180 is shaped so thathead 188 has a longitudinal axis that is parallel with and offset fromthe common longitudinal axis of the foot 182, torso 184 and neck 186. Acylindrical, pin-like nose 190 extends distally forward from head 188.Nose 190 has a diameter less than that of head 188. In some versions ofthe disclosure, the nose 190 has a diameter equal to that of the neck186. The longitudinal axis of the nose is aligned with the commonlongitudinal axis of the foot 182, torso 184 and neck 186.

When the pump 48 is assembled, shaft foot 182 is axially disposed insleeve 134. Drive shaft head 188 is disposed in the space between shellspanels 93 and 144. The drive shaft nose 190 is rotatably disposed in thebore 176 internal to distal shell boss 174.

A yoke 202, seen best in FIGS. 3 and 8, is slidably disposed betweenshells 92 and 142. More particularly, yoke 202 is slidably disposedbetween ribs 141 integral with proximal shell 92. Yoke 202 is formedfrom a set of webs and plates that, with one exception below, are notidentified. The yoke is formed to define an oval opening 204. Pump 48 isconstructed so that drive shaft head 188 seats within and can movewithin yoke opening 204.

Opposite the opening 204, yoke has an end plate 208. A notch 210 extendsinwardly from one side edge of end plate 208.

Spaced longitudinally away from the yoke end plate 208, pump 48 has astatic tube 250, now described by reference to FIGS. 8 and 9. Tube 250is formed from plastic and is cylindrical in shape. Tube 250 is formedto have a number of different sections. These sections define threecoaxial bores 252, 254, and 256 that collectively extend through thetube. Bore 252 is the bore closest to the yoke 202. Bore 256 is the borethat forms the open end of the bore adjacent the opening defined byshell indentations 98 and 154. Bore 254 is larger in diameter than bore252. Bore 256 is larger in diameter than bore 256.

Tube 250 is further formed to have a step 251 and an inner sleeve 257.Step 251 and inner sleeve 252 define bore 252. Step 251 and inner sleeve252 define an annular channel 258 that extends around and is isolatedfrom the coaxial bores 252, 254 and 256. Annular channel 258 openstowards yoke 202. Not identified is a small step that extends inwardlyfrom the inner sleeve 252. This step is located adjacent the open end ofbore 252. A fitting 260 extends diagonally away from tube 250. Fitting260 opens into annular channel 258.

A lip 262 extends radially outwardly from the main cylindrical body ofthe tube. Lip 262 is located around the end of the main body of the tubecloses to yoke 202. An annular ring 264 extends outwardly from lip 262towards yoke 202. Ring 264 is located inwardly from the outer perimeterof lip 262.

A tab 266 extends outwardly from the main cylindrical body of tube 250.Tab 266 is seated in a plane that is perpendicular to the longitudinalaxis of the tube 250. When pump 48 is assembled, tab 266 seats inproximal shell pylon slot 126. The seating of tab 266 in the pylon slot126 holds tube 250 as well as the components attached to the tube toproximal shell 92. When the tube 250 is disposed in the pump housing theend of the tube extends out of the opening defined by shell indentations98 and 154.

A duck billed valve 276 is seated in tube bore 252. Valve 276 isarranged so that the open end of the valve is directed towards the yoke202. The lips of the valve 276 are directed towards tube bore 254. Valve276 has a base 278 that extends radially outwardly from the valve aroundthe open end of the valve. Base 278 is curved in cross section. Theouter perimeter of the valve base 278 abuts tube lip 262. The componentsof the pump are arranged such that there is a small annular void spacebetween tube lip 262 and valve base 278. Tube annular channel 258 opensinto this void space.

A bellows 214 extends between yoke 202 and tube 250. Bellows 214 isformed from a flexible thermoplastic and has a cylindrical main body 215formed with circumferentially extending pleats (not identified). Bellowsbody 215 has a closed end adjacent yoke end plate 208. Bellows body 215has an open end directed to tube bore 252. A lip 216 extends radiallyoutwardly and circumferentially around the open end of bellows body 215.A ring 218 extends from the outer perimeter of lip 216 towards tube 250.More particularly, bellows ring 218 extends snuggly around ring 264integral with tube 250. An O-ring 220 is disposed over the outer surfaceof tube ring 264. The O-ring 220 is pressed between bellows lip 216 andtube ring 264. The O-ring 220 thus contributes to the seal between thebellows 214 and tube 250.

A button 217 extends outwardly from the closed end of bellows 214.Button 217 fits into the notch 210 integral with the yoke end plate 208to hold the bellows 214 to the yoke 202.

A solid cylindrical head 234 is disposed in the bellows body 215. Asmall crown 236 extend forward from the head. The crown 236 extends intoa void space in yoke button 217 (void space not identified). The headthus reciprocates with the reciprocation of the bellows 214.

Supply tube 40 extends from the irrigating fluid source 38 into the pumphousing through the opening defined by indentations shell indentations102 and 156. Immediately proximal to the distal end of the tube 40, thesuction tube is compression held to the housing in the spaces defined bythe cutouts integral with shell webs 118 and 164. The distal end ofsupply tube 40 is seated over tube fitting 260. The proximal end ofsupply tube 50 is fitted in tube bore 256. Supply tube 50 extends out oftube bore 256 and out of the pump housing through the opening defined byindentations 98 and 154.

Suction tube 66 extends through the pump housing. Proximally from wand52, the suction tube 66 extends into the pump housing through theopening defined by shell indentations 96 and 152. Within the pumphousing, the suction tube 66 is disposed within cutouts 108 integralwith webs 106 of the proximal sell 92 and the cutouts integral with theopposed webs 160 of distal shell 142. Suction tube 66 extends out of thepump housing through the opening defined by indentations 95 and 150.

Supply tube 50 is formed from PVC tubing. In some versions of thedisclosure, tube 50 resists radial expansion. This type of tube has arelatively high modulus of elasticity. Material hardness is generallyportion to the modulus of elasticity for tubing. Accordingly it isdesirable to provide a supply tube 50 that has a hardness of at leastShore A 80 and more often at least Shore A 100.

As seen by reference to FIGS. 10 and 11, wand 52 is constructed fromfirst and second shells 284 and 286, respectively. Internal to theshells 284 and 286 are webs 290, 292 and 294. Only the webs 290, 292 and294 in shell 284 are illustrated. Two longitudinally spaced apart webs290 are located towards the top of each shell 284 and 286. Each web 290is formed with a cutout (not identified). Four webs 292 are locatedtowards the bottom of each shell 284 and 286. Two of the webs 292 arelocated adjacent the distal ends of the shells. The third web 292 isspaced proximal from the first two webs. The fourth web 292 is spacedproximally from the third web 292. There are two webs 294 each of whichextends top to bottom within the shell 284 and 286. A first web 294forms the proximal end of the shell 284 and 286. A second web 294 islocated forward of the most proximal web and distal to the webs 290 and292.

Each web 294 is formed with two cutouts (not identified). Also notidentified are the bosses with bores internal to shells 284. While notillustrated it should be understood that shell 286 is formed withcomplementary bosses with bores. Not illustrated are the threadedfasteners that extend through these bosses so as to hold shells 284 and286 together.

A fitting 298 is seated in the forward end of the wand housing. Thefitting 298 is in the form of two contiguous rigid tubes. The fittingcomprises a proximal tube 302 and a distal tube 304. Distal tube 304 hasouter and inner diameters greater than the respective diameters of theproximal tube 302. Fitting 298 seats in the cutouts formed in webs 292.The distal end of the supply tube 50 extends into the proximal end ofthe wand housing. The supply tube 50 is lightly compression securedbetween webs 294 and the proximal most web 292. The distal end of thesupply tube 50 is seated in the bore internal to fitting proximal tube302. The proximal end of suction tube 66 is disposed in the wandhousing. The suction tube 66 is seated in the cutouts integral with webs290 and the top located cutouts integral with webs 294. Suction tube 66extends out of the wand housing above supply tube 48.

A tip lock 308 is moveably mounted to the wand 52. More specifically thetip lock 302 is sandwiched between shells 284 and 286. In the depictedversion of the disclosure, the tip lock is located forward of fitting298. The tip lock 308 contains features that releasably engagecomplementary features integral with tip assembly 58 so as to releasablyhold the tip assembly to the wand 52. In the depicted version of thedisclosure the tip assembly feature that the tip lock 302 engages is anarcuate rib 61 that extends partially circumferentially around thedischarge tube 59 forward of the proximal end of the tube. The exactstructure of the tip lock is not part of the present disclosure.

The bore internal to fitting distal tube 304 is dimensioned to receivethe proximal end of the tip assembly discharge tube 59. Seals, (notillustrated) may be fitted over the discharge tube 59 or disposed in thedistal tube 304. The seals prevent water leakage between the dischargetube 59 and fitting 298. Tip assembly suction tube 64 is formed to havea tapered head 67. The head is dimensioned to seat in the open end ofirrigator suction tube 66, the end seated in the distal end of wand 52.

Irrigator assembly 30 of this disclosure is prepared for use by fittinga tip assembly 58 to wand 52. Supply tube 40 is connected to irrigatingfluid source 38. Suction tube 64 is connected to suction device 72. Pumpassembly 48 is fitted the powered surgical tool 44. More particularly,this step is performed by inserting housing sleeve 134 in tool sleeve73. The complementary coupling features of the tool 44 and the housingsleeve 134 releasably hold the pump housing 86 to the tool 44. As aconsequence of the fitting of the pump assembly 48 to the tool 44, thepump drive shaft 180 seats in the tool drive spindle 68. Owing to thedimensioning of the components, the pump drive shaft 180 rotates inunison with the tool drive spindle 68.

Once the above steps are completed, irrigator assembly 30 is ready foruse The practitioner uses assembly 30 by pressing the tip assembly 58,often the open end of the spray shield 57, against the tissue to whichthe irrigating solution is to be applied. The practitioner dischargesthe solution by depressing the tool trigger 76. Upon detection that thetrigger 76 has been depressed, the control module 80 actuates the toolmotor 46. The resultant rotation of the drive spindle 68 results in alike actuation of the pump drive shaft 180. The rotation of the shaft180 results in the reciprocation of the pump bellows 214. Thereciprocation of the pump bellows results in fluid being drawn into thebellows through supply tube 40, fitting 260 and annular channel 258. Thefluid is forced out through supply tube 50. The fluid pumped throughsupply tube 50 is discharged from the wand 52 through the tip assemblydischarge tube 59. Simultaneously, suction is drawn through the tipassembly suction tube 64 and pump suction tube 66. This suction drawsthe discharge irrigation fluid as well as any waste entrained in thefluid to container 70.

Supply tube 50 being relatively hard is, while flexible, radially stiff(resists radial compression and radial expansion.) Owing to the radialstiffness of the supply tube 50, when a pulse of fluid is dischargedfrom pump 48, the pulse pressure does not appreciably expand the supplytube 50. Thus only a small fraction of the pulse pressure is attenuatedin the supply tube 50 as the pulse transits from through tube fordischarge out of the tip assembly.

Irrigator assembly 30 of this disclosure thus performs the irrigationand suction functions of a conventional irrigator. However, unlike manyconventional disposable irrigators, assembly 30 does not have a pumpmotor. Instead, the motor 46 internal to the tool 44 functions as thepump motor. Thus, in comparison to irrigators with their own pumps, itcan be more economical to provide irrigator assembly 30 of thisdisclosure.

It should further be appreciated that the motor 46 internal to the toolis more powerful than the use-once motor that is typically included witha conventional irrigator. More specifically, the motor 46 integral withthe tool is generally capable of outputting 60 Watts or more of power.This is typically two to five times the power that can be output by themotor contained in a conventional irrigator. Motor 46 therefore outputmore power to the pump 48 than is output by the motor of a conventionalirrigator. As a result pump 48 in comparison to the pump of aconventional irrigator is able to output fluid both at a higher flowrate and in pulses that have appreciably greater impact pressures.

Still another feature of irrigator assembly 30 is that surgical tool 44and wand 52 are separate components. This means the practitioner, withone hand, controls the on/off state of the assembly, by depressing thetool trigger 76 and, with the other hand, controls the position of thewand 52 and tip assembly 58. Often when the practitioner performs thesetasks, the tool 44 is simply resting on a static surface. So even thoughthe tool may weight in excess of 1 kg., the practitioner does not employmuscles to hold the tool in opposition to gravity. Only minimal motorskills are required to hold onto the tool 44 while simultaneouslypositioning the wand 52 and tip assembly 58. Since the wand and tipassembly typically weigh less than less than 0.3 kg and often less than0.15 kg, minimal muscle power is required to hold the tip assemblyagainst a wound or surgical site for periods of time exceeding 5minutes. Consequently, when the practitioner has to so hold the wand andtip assembly of this disclosure for these extended periods of time,there the likelihood that this individual will experience muscle fatigueor strain is substantially reduced.

Further wand 52 of this disclosure does not have a pump trigger, acomponent common with conventional irrigators. This feature of the wand52, in combination with the relatively low weight of the wand, makes itpossible for the practitioner to hold the wand in unusual positions,such as straight up or straight down, without appreciably adding to theeffort required to so position the wand.

Irrigator assembly 30 is also designed so that the assembly suction tube66 extends through the pump housing 86. This minimizes the extent towhich suction tube 66 moves away from complementary supply tube 50. Theholding of these tubes relatively close to each other reduces thepotential for other objects or the individuals attending to the patientbecoming tangled in the tubes.

It is still another feature of this disclosure, is the pump 48 isconfigured to convert the rotational motion of the tool drive spindle 68to reciprocating motion that is along an axis perpendicular to thelongitudinal axis of the drive spindle. This feature of the disclosureserves to hold the components internal to the pump 48 to a minimum.

As seen by comparing FIG. 12 to FIG. 1, pump housing 86 of thisdisclosure is designed so that the housing can be releasably coupled tothe tool 44 in plural orientations. In FIG. 1 the supply tube 50 extendsfrom the left side of the tool 44. Here this is the “left” side of thetool 44 from the perspective of the person holding the tool. In FIG. 12the supply tube 50 extends from the right side. This feature of assemblymeans that the assembly could be configured to personal preference ofthe individual using the assembly. If the practitioner wants to hold thetool, manipulate the trigger, using his/her right hand and position thewand with the left hand, the assembly can be set up as in FIG. 1. If thepractitioner wants to hold the tool, manipulate the trigger, usinghis/her left hand and position the wand with the right hand, theassembly can be set up as in FIG. 12. In either configuration the tubes40, 50 and 66 would be positioned in such a way to minimize thepractitioner's entanglement with the tubes.

Post procedure, only the wand, tubing, pump and tip assembly are subjectto disposal. There is no motor subject to disposal. A battery pack,which is often part of a conventional irrigator, likewise does notbecome an article of waste. An aspect of this feature of the disclosureis the current practice is to remove the batteries so they are disposedof separately from the plastic waste.

Tool 44, and only the tool, is sterilized using conventionalsterilization methods. It should be understood that if the tool isbattery powered, the battery 74 is of course also sterilized.

II. Second Embodiment

FIG. 13 illustrates an alternative pump assembly 360 of this disclosure.Assembly 360 includes tool 44, a transmission 380 and a pump cassette520. Transmission 380 is removably attached to tool 44, (battery 74 notshown). Transmission 380 converts the rotary motion of the drive spindle68 into a motion that reciprocates a drive pin 478. Cassette 520 isremovably attached to transmission 380. Internal to cassette 520 is apump 550 (FIG. 17). Tip assembly 58 extends forward from the cassette520. When the cassette 520 is fitted to transmission 380, the drive pin478 engages pump 550. Pump 550 draws irrigating fluid out of supply line40 and forces the fluid out of the cassette and the tip assemblydischarge tube 59.

As seen in FIG. 14, transmission 380 includes a housing that is formedfrom right and left shells 382 and 412, respectively. When assembledtogether, the shells 382 and 412 form a sleeve 418. Sleeve 418 isdimensioned to fit in tool sleeve 73. Sleeve 418 is formed with at leastone feature that, in cooperation with the coupling features integralwith tool 44, facilitate the releasable attachment of transmission 380to the tool. One of these features, a slot 419, is partially seen inFIG. 14. The transmission housing is shaped so that when thetransmission is secure to the tool, the main portion of the housing isdisposed on top of tool barrel 65.

Internal to the transmission housing is a gear train 430 to which adrive link 470 is connected. Drive pin 478 is connected to the proximalend of the drive link to move with the drive link 470. Gear trainconverts the rotary motion output by the tool drive spindle 68 intomotion that reciprocates drive link 470 and drive pin 478.

FIG. 15 depicts the inside of transmission right shell 382, the leftshell 412 having generally a mirror image geometry of the right shell382. Shell 382 is formed to have a semi-circular half-sleeve 384. Thehalf-sleeves of shells 382 and 412 collectively forming sleeve 418.Distally forward half-sleeve 384 shell 382 has a head 386. Head 386extends outwardly from half-sleeve 384. An arm 388 extends proximallyfrom head 386. Arm 388 is spaced above and extends proximally rearwardfrom half-sleeve 384. When the transmission 380 is mounted to tool 44,the sleeve heads 386 are the portion of the transmission housing thatare located forward of tool sleeve 73. The sleeve arms 388 arecollectively the section of the transmission housing that extends overtool barrel 65. In some versions of the disclosure, the transmissionhousing is formed so that the sleeve arms 388 are disposed a smalldistance, typically 3 mm or less above the outer surface of the toolbarrel 65.

A rib 385 extends upwardly from the shell head 386. Rib 385 is, crosssection generally shaped like the upper half of the letter C. Rib 385 isspaced above arm 388 so as to extend a short distance over the distalend of arm 388. A post 387 extends upwardly from the outer surface ofarm 388.

Each shell 382 and 412 is formed with a number of void spaces. A set ofvoid spaces 389, 390, 391, 392 and 393 extend along a line coincidentwith the longitudinal axis of half-sleeve 384. Void spaces 389 and 390as well as the proximal end of void space 391 are disposed inhalf-sleeve 384. The distal portion of void space 391 and void spaces392 and 393 are located in shell head 386. A set of void spacescollectively identified by identification number 394 are also formed insleeve head 386. These void spaces are centered on an axis perpendicularto the axis along which void spaces 389-393 are centered. These voidspaces are generally located above void spaces 389-393. One of thesevoid spaces intersects void space 393.

Each shell 382 and 412 is further formed to have an elongated slot 395.The slot 395 extends from the top most one of the void spaces 394proximally so as to extend through arm 388. The distal end of the slot395 is elevated relative to the middle and proximal sections of the slot395. Slot 395 terminates in an opening 396 formed in the arm 388.Opening 396 opens into the top surface of the arm 388.

Transmission shells 382 and 412 are further formed to have asymmetricnotches 402 and 404, respectively. Notches 402 and 404 are locatedimmediately forward of the proximal end of arms 388. The width of notch402, the length perpendicular to the longitudinal axis of arm 388, isgreater than the width of notch 404. Arm 388 is further formed so thatthere is small undercut (not illustrated) integral with notch 404 belowthe surface of the arm 388.

Fasteners 413 are used to secure shells 382 and 412 together. Notidentified are the geometric features integral with the shell 382 and412 in which the fasteners are seated. When the shells are securedtogether, the void spaces 389-394 and slot 395 of shell 382 meet thecomplementary void spaces 389-394 and slot 395 of shell 412. Thecontiguous void spaces form bores internal to the transmission housing.The contiguous slots 395 form a single elongated slot below the topouter surface of the transmission housing.

Returning to FIG. 14 it can be seen that gear train 430 includes aninput shaft 432. Input shaft 432 is rotatably disposed in the boreformed the transmission housing by shell void spaces 389-392. Bearingassemblies 434 and 435 rotatably hold the input shaft 432 in thetransmission housing. While not identified, the proximal end of inputshaft 432 includes features that engage the tool drive spindle 68 sothat shaft 432 rotates with the drive spindle 68. A beveled gear 438 ismounted to the distal end of input shaft 432. Gear is disposed in thetransmission housing bore formed by void spaces 393.

An output shaft 448 is also rotatably disposed in the transmissionhousing. Shaft 448 is disposed in the bores defined by void spaces 394.Bearings 449 and 450 rotatably hold the shaft in the transmissionhousing. A beveled gear 446 is disposed to the end of shaft 448 locatedfurthest within the head of the transmission housing. Output shaft 448is formed to have a main body 450 and a head 452 both of which aregenerally cylindrical. The longitudinal axis of the head 452 islaterally offset from the longitudinal axis of the main body 450. Whentransmission 380 is assembled, head 452 is located in the topmost boreof void space 394, the bore that intersects the void space internal tothe transmission head formed by the contiguous slots 395.

From FIG. 16 it can be seen that drive link 470 is generally in the formof an elongated bar. A ring 469 is located at the distal end of thelink. Ring 469 is elevated and parallel to the main body of the body ofthe link. Not identified is the angled front end of the bar that formsthe transition from ring 469 to the main body of the bar. Link 470 isfurther formed to have a proximal end ring 472. When the transmission isassembled, link 470 is slidably disposed in the void space formed by thecontiguous shell elongated slots 395. Distal end ring 469 is seated overthe head 452 of output shaft 448. The proximal end ring 472 is seatedbelow the opening 396 formed in the transmission housing.

Drive pin 478 is generally in the form of cylindrical structure. A lip480 extends radially outwardly and circumferentially around the base ofthe pin. Drive pin 478 extends through the opening integral with theproximal end ring 472 integral with the drive link 470. In some versionsof the disclosure, pin 478 is press fit through ring 472. The drive pin478 extends out through the transmission housing opening 396 so as toproject above the transmission housing

Cassette 520, as seen in FIG. 17, includes a housing that consists oftop and bottom shells 522 and 562, respectively. Internal to thecassette housing is a moveable latch 602, pump 550 and a tip lock 662.Latch 602 seats in notches 402 and 404 to releasably hold the cassette520 to the transmission 380. When the cassette 520 is so secured,transmission drive pin 478 extends through an opening 570 in bottomshell 562. The drive pin 478 engages pump 550. Tip lock 662 releasablyholds tip assembly 58 to the cassette 520.

Top shell 522 is formed to have at the proximal end, a pair of curvedfeet 523. Feet 523 are symmetric along a plane extending verticallythrough the longitudinal axis of the shell 522. Each foot 523 extendsfrom an outer side of the shell 522 and curves inwardly towards thecenter of the shell. The ends of the feet 523 are spaced apart from eachother. Top shell 522 is further formed to have rib 524 that extendsupwardly from the surface of the shell. Rib 524 is located between feet523. The rib 524 is shaped to have opposed longitudinally extendingouter surfaces that have a concave curvature, (surfaces not identified).Feet 523 and rib 524 are spaced apart from each other so supply tube 40can be held, lightly compressed between one foot 523 and the rib andsuction tube 66 can similarly be held between the other foot 523 and therib.

As seen best in FIG. 18, cassette bottom shell 562 has a planar basesurface 564. The cassette bottom shell 562 is dimensioned to seat on theadjacent outer surfaces of the arms 388 integral with transmission 380.A lip 566 projects forward from and the shell base surface 564. Lip 566is dimensioned to closely slip fit within the space between thetransmission housing ribs 385 and underlying arms 388. Bottom shell 562is further formed so that there are two small diameter circular openings568 in base surface 564. When cassette 520 is seated on transmission380, each transmission post 387 seats in a separate one of the cassetteopenings 568. The bottom shell 562 is further formed so that, slightlyforward of the proximal end of the shell there is an oval opening 570.The major axis of opening 570 is parallel to if not aligned with thelongitudinal axis of pump 550. Opening 570 is positioned and dimensionedto receive drive pin 478. The opening 570 is further dimensioned so thatthe drive pin 478 can move longitudinally in the opening 570.

Cassette bottom shell 562 is further formed to have an opening 572.Opening 572 is located between the proximal end of the shell 562 andopening 570. The bottom shell 562 is formed so that opening 572 isrectangular in shape and orientated so that the major axis of theopening is perpendicular to the longitudinal axis of the cassette 520.The cassette 520 is further shaped so that when the cassette 520 ismounted to the transmission 380 opening 572 extends at least partiallyover the opening formed by notches 402 and 404 integral with thetransmission 380.

As seen in FIG. 19, internal to the bottom shell 562 there is agenerally rectangular void space 574. Openings 570 and 572 open intovoid space 574. Immediately forward of the proximal end of the shell 562a three sided frame 578 extends laterally away from one side of theshell. Frame 578 defines a recess 580. Inward of frame 578 the shell hasa web 581. Web 581 defines the base of recess 580. Web 581 does notextend completely across the frame 578. Instead, the web terminatesdistal to the proximal end wall of the shell 562. Consequently, there isa small gap between the proximal end wall of the shell 562 and web 581,(gap not identified).

A web 582 with an arcuate cutout (not identified), extend into voidspace 574. Distally forward of void space 574, bottom shell is formedwith an inwardly shaped arcuately recessed surface 584. A rectangularslot 586 extends inwardly from surface 584. The major axis of slot 586is perpendicular to the longitudinal axis through the shell 562.

Latch 602, as seen in FIG. 21, is formed from a single piece of plastic.The latch has a main body 604, of generally rectangular shape. A firstfoot, foot 606 extends away from one end of the body 604 so as to extendacross and away from the end of the body to which the foot is attached.Foot 606 is able to flex relative to body 604. A second foot, foot 608extends outwardly from one of the side edges of the body. Moreparticularly foot 608 extends away from the side of the body 604 fromwhich foot 606 extends. Foot 608 is formed with a toe 610 that extendsforward from the portion of the foot that extends away from the latchmain body 602.

The latch 602 is further formed to have a rib 611. Rib 611 extendslaterally across the main body 604. Rib 611 extends across the latchmain body 604 at a location close to the end of the main body oppositethe end of the body from which foot 606 extends. Latch 602 also has ahead 612. The head extends outwardly from the major surface of the body604 from which rib 610 extends. A reinforcing web 614 extends from aside edge of the main body 604 to head 612.

Latch 602 is slidably mounted in cassette bottom shell 562. Moreparticularly, the latch is mounted within the shell 562 so that theflat, featureless main surface of the latch main body 604 is disposedagainst the inner surface of the proximal wall of the shell 562. Foot606 abuts the inner surface of the side wall opposite the side of theshell from which frame 578 extends. Foot 610 extends out of shellopening 572. The end of latch main body 604 opposite foot 606 extendsthrough the gap between the shell proximal wall and 581. Latch head 612is seated in recess 580.

Owing to the dimensioning of bottom shell 562 and latch 602, foot 606normally places a force on the rest of the latch 602 that pushes therest of the latch away from the side wall of the shell against which thefoot 606 abuts. The outward movement of the latch 602 is limited by theabutment of latch rib 611 against the inner surface of shell web 581.

Pump 550 is generally similar in structure to previously described pump48. The yoke 552 and bellows 554 of pump 550 are disposed in the voidspace of bottom shell void space 574. The pump static tube 556 is seatedagainst shell recessed surface 584. The tab 558 integral with the outertube seats in shell slot 586.

Tip lock 662 is moveably mounted to shells 522 and 562 in a spaceimmediately proximal to the front face of the cassette housing formed bythe shells.

From FIG. 13 it can be seen that supply tube 40 is seated between theleft side foot 523 and rib 524. While not illustrated it should beunderstood the supply tube 40 extends into the cassette housing throughthe channel defined top and bottom shell grooves 528 and 596,respectively. The distal end of the supply tube is attached to thefitting 560 integral with pump static tube 556.

A suction tube, not illustrated, is sandwiched between shells 522 and562. The suction tube extends from a location adjacent the opening in adistally directed wall of the top cassette housing into which the tipassembly suction tube 64 is seated. The suction tube extendssubstantially linearly through the cassette housing. The suction tubeextends proximally out of the housing through the bore formed by top andbottom shell grooves 330 and 598, (FIG. 18) respectively.

Fasteners 690 hold shells 522 and 562 together. Not identified are thegeometric features of the shells 522 and 562 in which the fasteners 690are seated.

Assembly 360 is readied for use by first fitting transmission 380 to thetool 44. Cassette 520 is fitted over the transmission 380. This processis initially performed by seating the cassette lip 566 into the voidspace below transmission ribs 385. This serves to secure the distal endof the cassette 520 to the transmission 380. The cassette is pivoteddownwardly to cause transmission pins 37 to seat in cassette bores 568.The continued movement of the cassette 520 against the transmissionresults in latch toe 610 seating in the undercut integral withtransmission notch 404. During this part of the attachment process foot606 is momentarily compressed. This engagement releasably holds thecassette 520 to the transmission 380. As a consequence of thispositioning of the cassette 520, transmission drive pin 478 seats inpump yoke 552.

The assembly is positioned so that the tip assembly 58 is locatedadjacent the site to which the irrigating fluid is discharged. Tooltrigger 76 is depressed. The resultant actuation of the tool motor 46results in the actuation of cassette pump 550. The actuation of the pump550 results in the discharge of the irrigating fluid from discharge tube59.

Once assembly 360 is used in a procedure, the cassette 520 is removedfrom the transmission 380 for disposal of the cassette. To decouple thecassette 520 from transmission 380, finger force is applied againstlatch head 612. This finger force overcomes the spring force of foot 606so as to cause the displacement of the latch. The displacement of thelatch withdraws toe 610 from the undercut in the transmission in whichthe toe is seated. This repositioning of latch 602 allows the cassette520 to be lifted off the transmission.

Assembly 360 is constructed so that the transmission 380 is disposedabove the tool 44 and the cassette 520 is disposed above thetransmission. This means that the center of gravity of the assembly, thetool 44, the transmission, 380, the cassette 520 and the tip assembly 58are located relatively close to the handgrip 69, the portion of theassembly held and manipulated by the practitioner. Ergonomically, thisreduces the muscle strain to which the practitioner is exposed whenholding the assembly 380 against a site for an extended period of time.

Similarly it should be understood that in this version of thedisclosure, the distal end of the tip assembly is typically located amaximum of 30 cm from the front of the handgrip 69 (along a longitudinalaxis through the assembly). More preferably this distance is at the most25 cm and still even more preferably no more than 20 cm. One advantageof the assembly 360 of this disclosure being compact in this dimensionis that it reduces the efforts required to position the distal end ofthe tip assembly when the practitioner has to target surfaces that arerelative to the practitioner chest high or higher. This type ofpositioning is known to occur when an irrigator is used to clean tissuein a total knee replacement procedure and the knee is in flexion.

Further there is still a further benefit of the assembly 360 of thisversion of the disclosure being compact along this axis. The suctiondrawn through tip assembly 58 and cartridge 520 can be of sufficientstrength to cause the tip assembly to essentially adhere to the tissueto which the assembly is applied. If there is an appreciable distancebetween this interface and the handgrip 69, when it is desirable toshift the position of the tip assembly, the practitioner may have toapply a significant amount of torque to the handgrip to overcome theresistive suction force. If this distance is relatively short, lesstorque is applied to the tool handgrip 69 so reposition the tip assembly58.

Still another feature of this version of the disclosure is that in thecassette there is substantially no bending of the suction tube in thecassette. The longitudinal axis through the distal most 2 cm of the tubewithin the cassette is offset by less than 30° and often less than 10°from the longitudinal axis through the proximal most 2 cm of the tube.In many versions of the disclosure, the suction tube extends linearlythrough the cassette 520. The length of the section of the tube withinthe cassette, the section to which the tip assembly suction tube 64 isattached, has a length of at least 10 cm. Since there is minimal or nobending of the suction tube within this section of the suction tube,there are essentially no bends that can serve as locations where debrisentrained in the waste stream withdrawn from the site through assembly360 can clog the suction line. Further the straight through or at leastessentially straight flow suction ensures a high flow rate as comparedto the flow rate through the same length of tube that is appreciablybent.

As with the first embodiment of the disclosure the presence of thesuction tubes eliminates the need to provide a separate suction wand forcollecting the fluid discharged by the irrigator assembly of thisdisclosure.

The presence of the tip lock reduces the likelihood that during theprocedure the tip assembly 58 will inadvertently separate from thecassette 520. If this separation occurs during the procedure, theseparation could result in an uncontrolled release of irrigating fluid.This fluid could contaminate the surrounding environment. The fluidcould potentially even contaminate the surgical site to which theirrigating fluid was being applied.

Cassette 520 is further positioned to minimize the likelihood that thetubes connected to the cassette will somehow approach the tool handgrip69. This reduces the likelihood that the tubes will somehow come soclose to the trigger that they will interfere with the practitioner'sactuation of the trigger.

In many versions of this disclosure, transmission 380, the sub-assemblythrough which fluid is not flowed, is formed out of components that aresterilizable. The pump 520, which is the sub-assembly through whichfluid is flowed is formed out of components that are often notsterilizable. Generally, it is more expensive to construct a devicethrough which fluid is flowed out of sterilizable components. Thus, amadditional feature of many versions of pump assembly 360 is that it canbe more economical to provide the transmission 380 of this disclosureand sterilize the transmission for reuse than to provide with atransmission formed out of non-sterilizable components that is designedfor a single use.

II. Alternative Embodiments

It should be appreciated that the above is directed to specific versionsof the disclosure. Alternative irrigating assemblies of this disclosuremay be proved.

The features of the different versions of this disclosure may becombined. For example, wand 52 of the first embodiment can be added tothe assembly 360 of the second embodiment, Alternatively not allversions of this disclosure may use each of the features disclosed withregard to the two described versions of the disclosure.

For example, there is no requirement that the tool integral with thesystem be a battery powered power tool. The system of this disclosuremay include an electrically driven power tool that receives its powerfrom a remote console over a cord. Alternatively, the tool integral withthis system may include a pneumatically or hydraulically driven motor.

Also, it is often desirable to attach a clamp to the suction tube 66.This clamp is selectively closed to prevent suction drawn when it is notdesired by the practitioner. When suction is not desired this alsominimizes suction noise. Further, negating the suction draw can, in somesituations reduce the extent to which airborne contaminates are drawntowards the site to which the tip assembly is applied.

Similarly, while seldom employed, some irrigators of this disclosure maynot include a means for drawing discharged fluid from the site to whichthe irrigating fluid is discharged. This would eliminate the need toprovide the suction tube 66 and like features for holding the suctiontube to the rest of the assembly. In versions of the assembly in whichthe suction tube 66 is present, it may not always be necessary to threadthe suction tube through the pump housing.

In many versions of the disclosure, supply tube 50 and suction tube 66may be bonded or clipped together. Holding these tubes in tandem reducesthe likelihood of these tubes tangling with each other, other equipmentor the practitioner. For the same reason at least the section of supplytube 40 adjacent the pump and the adjacent section of the suction tube66 may likewise be bonded or clipped together. In these and outerversions of the disclosure there might not be a need to thread thesuction tube through the pump housing 86.

There is no requirement that all versions of the disclosure the wand andtip assembly be separate components. In versions of the disclosure inwhich these components are a unified assembly the need to provide a tipfitting and or tip lock may be eliminated.

Further it may be necessary to form supply tube 50 out of homogenousplastic that has the desirable modulus of elasticity, that resistsradial deformation. Supply tube 50 can be formed out of tube withinternal braiding or fibers that resist radial expansion. For economicsof manufacture, it may not be necessary to supply tube 40 or the suctiontube 66 out of material that is as radially stiff as supply tube 50.

Likewise, the type of pump integral with this disclosure is not limitedto bellows pump. Other positive displacement pumps such as piston pumpsor pumps with a diaphragm may be incorporated into this disclosure.Similarly this disclosure is not limited to a pump wherein the movingelement reciprocates back and forth. Some versions of this disclosuremay include pumps wherein the pumping element engages in rotary motion.Examples of such pumps are vane pumps and impeller pumps. Further insome versions of the disclosure the pump may be a peristaltic pump.

Each of the above types of pumps it is understood may have atransmission assembly different from what has been disclosed to convertthe rotary output of the tool into motion that drives the pump. Forexample in some versions of the disclosure wherein the pump has a rotarypumping element, the transmission assembly may include a set of gearsthat decrease the speed/increase the torque that is applied to thepumping element.

Likewise, in some versions of the disclosure the transmission may actualrest on the surface of the housing of the tool to which transmission isremovably attached.

Further while the suction tube may extend linearly or substantiallylinearly through the wand or cassette, there is no requirement that thetube extend along an axis or lie in a plane that is parallel to thelongitudinal axis of the wand or cassette.

Other means than the disclosed fasteners may be used to secure thevarious shells together that form the housings of the components of thisdisclosure. For example, snap fasteners, adhesives and welding may beemployed to hold the components of this disclosure together. Likewise,there is no requirement that the shells that are substantially mirrorversions of each other always be mirror versions of each other.

Similarly, in versions of the disclosure wherein the pump and associatedtransmission are mounted to the top of the handpiece 44, there is norequirement that these two sub-assemblies have separate housings. Insome versions of this disclosure these sub-assemblies may be containedin a single housing. This housing as well as the components it contains,may be either sterilizable and reusable or a single use disposabledevice.

Likewise, in versions of the disclosure wherein the pump andtransmission assembly are configured to extend at least partially overthe associated tool 44, there is no requirement that the pump always beseated on top of the transmission assembly. In some versions of thedisclosure, the pump components may be substantially linearly alignedwith at least some of the transmission components.

In versions of the disclosure wherein at least some of the componentsare replaceable, these components may be removably seated in a cavityformed in the housing of the transmission assembly.

Accordingly, it is an object of the appended claims to cover all suchvariations and modifications that come within the true spirit and scopeof this disclosure.

What is claimed is:
 1. A transmission for use with a powered surgicaltool, the powered surgical tool having a body and a rotating drivespindle that extends from the body and is configured to releasablyreceive and drive an implement, said transmission comprising: a housing;an input shaft adapted to releasably engage the drive spindle of thepowered surgical tool, wherein said housing has a feature for releasablyattaching said housing to the body of the powered surgical tool so thatwhen said housing is attached to the powered surgical tool, said inputshaft is releasably engaged with the drive spindle so as to be ableconvert an output moment of the drive spindle; and said housing beingconfigured to at least partially extend over a portion of the poweredsurgical tool when said housing is attached to the body of the poweredsurgical tool.
 2. The transmission of claim 1, further comprising adrive link disposed in said housing for reciprocating movement withinsaid housing.
 3. The transmission of claim 2, comprising a gear traindisposed within said housing, said gear train including said inputshaft, said gear train is connected to said drive link and is adapted toconvert a rotary motion of said input shaft into motion thatreciprocates said drive link.
 4. The transmission of claim 3, whereinsaid housing is shaped to have a head and an arm, said head being shapedto be coupled to a distal end of the powered surgical tool, and said armextends proximally from said head and positioned to extend over an outersurface of the body of the powered surgical tool when said housing isattached to the body of the powered surgical tool.
 5. The transmissionof claim 4, wherein said arm has a top surface with an opening.
 6. Thetransmission of claim 5, wherein said drive link is disposed in saidhousing so as to be disposed for reciprocating movement in said arm sothat said drive link extends over the body of the powered surgical tool.7. The transmission of claim 5, wherein said housing comprises a featurefor releasably attaching a device to said top surface of said arm. 8.The transmission of claim 7, wherein said feature for releasablyattaching the device is a rib that extends outwardly from said housing.9. The transmission of claim 7, wherein said feature for releasablyattaching the device is a post that extends outwardly from said housing.10. The transmission of claim 2, wherein said drive link comprises afeature for engaging a driven component of a pump cassette.
 11. Thetransmission of claim 10, wherein said housing includes a feature forreleasably attaching a pump cassette to said housing.
 12. Thetransmission of claim 2, further comprising a drive pin connected tosaid drive link.
 13. The transmission of claim 1, further comprising apump for pumping an irrigating fluid.
 14. The transmission of claim 13,further comprising a tip assembly having a discharge tube for connectionto said pump for receiving irrigating fluid pumped by said pump throughwhich irrigating fluid can be applied to a site on a patient.
 15. Atransmission for use with a powered surgical tool, the powered surgicaltool having a body and a rotating drive spindle that extends from thebody that is configured to releasably receive and drive a cuttingimplement, said transmission comprising: a housing shaped to have ahead, said head being shaped to be coupled to a distal end of the tooland an arm that extends proximally from the head, said arm beingpositioned to extend over an outer surface of the body, said arm havinga top surface with an opening, the top surface adapted to receiveanother device so that the other device extends over the body; a firstfeature attached to the head of said housing for releasably attachingsaid housing to the body; a second feature attached to said housing forreleasably holding the device to said top surface of said arm; and agear train internal to said housing, said gear train including arotating input spindle disposed in said head of said housing forengaging the rotating drive spindle of the powered surgical tool; adrive link disposed in said arm of said housing for reciprocatingmovement so that said drive link extends over the body of the poweredsurgical tool, said drive link including a driven component for engagingthe other device, said driven component accessible through said openingin said top surface of said arm; and a gear assembly configured toconnect said input spindle to said drive link so that the rotation ofsaid input spindle results in the reciprocation of said drive link. 16.The transmission of claim 15, wherein a drive pin is connected to saiddrive link and said drive pin is a drive link feature that releasablyengages a driven component of the other device to be attached to saidhousing.
 17. The transmission of claim 15, wherein said driven componentis a yoke.
 18. A powered surgical tool system, said system comprising: apowered surgical tool having a tool body and a rotating drive spindlethat extends from said body and is configured to drive an implement; atransmission comprising a housing and an input shaft, said input shaftadapted to releasably engage said rotating drive spindle of said poweredsurgical tool, said housing having a feature for releasably attachingsaid housing to said tool body of the powered surgical tool so that whensaid housing is attached to said powered surgical tool, said input shaftis releasably engaged with said rotating drive spindle of said poweredsurgical tool so as to be able convert an output moment of said rotatingdrive spindle; and said housing is configured to at least partiallyextend over a portion of the powered surgical tool.
 19. The system ofclaim 18, further comprising a pump cassette, wherein said housingincludes a feature for releasably attaching said pump cassette to saidhousing.
 20. The system of claim 18, wherein said housing is shaped tohave a head and an arm, said head being shaped to be coupled to a distalend of said powered surgical tool, said arm being positioned to extendover an outer surface of said body of said powered surgical tool,wherein said arm has a top surface with an opening.